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+/*
+ * Copyright (c) 1988, 1989, 1990, 1993
+ * The Regents of the University of California. All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Adam de Boor.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by the University of
+ * California, Berkeley and its contributors.
+ * 4. Neither the name of the University nor the names of its contributors
+ * may be used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#ifndef lint
+static char sccsid[] = "@(#)lstDeQueue.c 8.1 (Berkeley) 6/6/93";
+#endif /* not lint */
+
+/*-
+ * LstDeQueue.c --
+ * Remove the node and return its datum from the head of the list
+ */
+
+#include "lstInt.h"
+
+/*-
+ *-----------------------------------------------------------------------
+ * Lst_DeQueue --
+ * Remove and return the datum at the head of the given list.
+ *
+ * Results:
+ * The datum in the node at the head or (ick) NIL if the list
+ * is empty.
+ *
+ * Side Effects:
+ * The head node is removed from the list.
+ *
+ *-----------------------------------------------------------------------
+ */
+ClientData
+Lst_DeQueue (l)
+ Lst l;
+{
+ ClientData rd;
+ register ListNode tln;
+
+ tln = (ListNode) Lst_First (l);
+ if (tln == NilListNode) {
+ return ((ClientData) NIL);
+ }
+
+ rd = tln->datum;
+ if (Lst_Remove (l, (LstNode)tln) == FAILURE) {
+ return ((ClientData) NIL);
+ } else {
+ return (rd);
+ }
+}
+
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